This disclosure generally relates to characterizing of fluids present in hydrocarbon wellbores. In particular, this disclosure relates to systems and methods for measuring and simulating optical sensor response data associated with fluids in a wellbore.
When performing subterranean operations in wellbores, it is often desirable to obtain information about the subterranean formation, including information regarding the fluids present in the formation. During sampling and testing the formation, for instance, formation fluid may be drawn from the formation and passed by a downhole optical tool (e.g., an optical sensor incorporated on a wireline formation tester). The downhole optical tool may be designed with a number of optical channels to measure optical responses from the fluid as a function of the wavelength of the light. The data from these optical channels can then be processed as inputs to fluid characterization models for estimation of fluid properties such as fluid composition, density, or viscosity.
The fluid characterization models are usually pre-determined from a database of laboratory-measured spectral data at various temperatures and pressures transformed to estimate fluid compositions and other properties. To apply the measured optical tool data to the fluid models directly, the fluid models may need to be calibrated in actual sensor parameter spaces, requiring optical feature mapping from the database to the corresponding sensor database through a transformation algorithm before developing the fluid characterization models. The data transformation, however, may be difficult to achieve depending on the difference between the synthetic sensor and actual sensor responses, the number and the type of reference fluids used for modelling transformation algorithm, the features selected as attributable input and output of mapping function, and the robustness of the transformation in dealing with interpolated and extrapolated optical fluid responses.
While embodiments of this disclosure have been depicted and described and are defined by reference to example embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.